replaces 'size() == 0' and 'length() == 0' with 'isEmpty()'

src/main/java/org/apache/commons/lang3/ClassUtils.java

@@ -1347,7 +1347,7 @@ public class ClassUtils {
                     ? className.length() - 1
                     : className.length());
         } else {
-            if (className.length() > 0) {
+            if (!className.isEmpty()) {
                 className = reverseAbbreviationMap.get(className.substring(0, 1));
             }
         }

src/main/java/org/apache/commons/lang3/LocaleUtils.java

@@ -150,8 +150,8 @@ public class LocaleUtils {
             final String country = segments[1];
             final String variant = segments[2];
             if (isISO639LanguageCode(language) &&
-                    (country.length() == 0 || isISO3166CountryCode(country) || isNumericAreaCode(country)) &&
+                    (country.isEmpty() || isISO3166CountryCode(country) || isNumericAreaCode(country)) &&
-                    variant.length() > 0) {
+                    !variant.isEmpty()) {
                 return new Locale(language, country, variant);
             }
         }
@@ -227,10 +227,10 @@ public class LocaleUtils {
         final List<Locale> list = new ArrayList<>(4);
         if (locale != null) {
             list.add(locale);
-            if (locale.getVariant().length() > 0) {
+            if (!locale.getVariant().isEmpty()) {
                 list.add(new Locale(locale.getLanguage(), locale.getCountry()));
             }
-            if (locale.getCountry().length() > 0) {
+            if (!locale.getCountry().isEmpty()) {
                 list.add(new Locale(locale.getLanguage(), StringUtils.EMPTY));
             }
             if (!list.contains(defaultLocale)) {
@@ -330,7 +330,7 @@ public class LocaleUtils {
             final List<Locale> locales = availableLocaleList();
             for (final Locale locale : locales) {
                 if (languageCode.equals(locale.getLanguage()) &&
-                    locale.getCountry().length() != 0 &&
+                        !locale.getCountry().isEmpty() &&
                     locale.getVariant().isEmpty()) {
                     countries.add(locale);
                 }

src/main/java/org/apache/commons/lang3/builder/DiffResult.java

@@ -170,7 +170,7 @@ public class DiffResult implements Iterable<Diff<?>> {
      * @return a {@code String} description of the differences.
      */
     public String toString(final ToStringStyle style) {
-        if (diffs.size() == 0) {
+        if (diffs.isEmpty()) {
             return OBJECTS_SAME_STRING;
         }
 

src/main/java/org/apache/commons/lang3/exception/DefaultExceptionContext.java

@@ -130,7 +130,7 @@ public class DefaultExceptionContext implements ExceptionContext, Serializable {
             buffer.append(baseMessage);
         }
 
-        if (contextValues.size() > 0) {
+        if (!contextValues.isEmpty()) {
             if (buffer.length() > 0) {
                 buffer.append('\n');
             }

src/main/java/org/apache/commons/lang3/math/NumberUtils.java

@@ -526,7 +526,7 @@ public class NumberUtils {
                 case 'L' :
                     if (dec == null
                         && exp == null
-                        && (numeric.length() > 0 && numeric.charAt(0) == '-' && isDigits(numeric.substring(1)) || isDigits(numeric))) {
+                        && (!numeric.isEmpty() && numeric.charAt(0) == '-' && isDigits(numeric.substring(1)) || isDigits(numeric))) {
                         try {
                             return createLong(numeric);
                         } catch (final NumberFormatException nfe) { // NOPMD
@@ -661,7 +661,7 @@ public class NumberUtils {
                 return false;
             }
         }
-        return str.length() > 0;
+        return !str.isEmpty();
     }
 
     //-----------------------------------------------------------------------

src/main/java/org/apache/commons/lang3/text/StrLookup.java

@@ -171,7 +171,7 @@ public abstract class StrLookup<V> {
          */
         @Override
         public String lookup(final String key) {
-            if (key.length() > 0) {
+            if (!key.isEmpty()) {
                 try {
                     return System.getProperty(key);
                 } catch (final SecurityException scex) {

src/main/java/org/apache/commons/lang3/time/DurationFormatUtils.java

@@ -195,7 +195,7 @@ public class DurationFormatUtils {
                     }
                 }
             }
-            if (duration.length() != 0) {
+            if (!duration.isEmpty()) {
                 // strip the space off again
                 duration = duration.substring(1);
             }